Two fishery administration vessels reached the Nantong section of the Yangtze River on September 21 as part of the fourth scientific survey of Yangtze finless porpoises, which is also the first after the implementation of the 10-year fishing ban in pivotal waters of the Yangtze River.

As the sole cetacean living in the Yangtze River, the species is an important indicator of the river’s ecological health, with vital conservation importance and research value.

"Compared to the three previous surveys, two new technologies of imaging and eDNA will help get a bigger picture of the species’ population and distribution and environmental status of the habitat," said Jiang Meng, secretary-general of Nanjing Finless Porpoise and Aquatic Life Conservation Association.

Zheng Jinsong, researcher at the Institute of Hydrobiology (IHB) of the Chinese Academy of Sciences (CAS), collected water sample for eDNA analysis while working on the vessel. Zheng said the analytical tool can obtain information released by different species.

There were 1,800 finless porpoises in the river according to the 2006 survey, and approximately 1,040 in 2012 and 1,012 in 2017. Protection efforts have halted the sharp decline in the species population but not changed its status of being critically endangered.

(Photo/Ding Weiwen)

The research vessel sails for about 10 hours a day, and it can be tiring to stare at the river and instruments on board for a long time, said Li Jianhua of Shanghai Ocean University. However, he added that the moment of seeing the porpoise is the most exciting and fulfilling thing for a researcher.